> Now that you bring it up, the E programmer could indeed use this trick to
> make all the pre/post-condition,invariants,requires patterns I explained
> earlier explicitly switchable, negating my claim that Eiffel had a real
> advantage here. Cool.
To me the important feature of DBC is that the class's interface, as
perceived by the programmers that invoke it or that edit its source
code, is more richly expressed.
The actual run-time checking of those constraints is not as important
as the fact that the design is communicated explicitly among
programmers.
For E to be strictly better than Eiffel in this regard, it would need
to have standard conventions for DBC that all E programmers learned,
and a standard tool that extracted the interface and included the DBC
constructs.
Regards,
Zooko